On Erev Yom Kippur (the 9th of Tishrei, in the early morning we
do the Kapporos Service. (See the Machzor - special prayer book for
the days of awe for detail.)

Later on during the day we eat the festive meals, to demonstrate our
faith and confidence in G-d's mercy.

Another beautiful custom for this day is that of parents blessing
their children with the Priestly Benediction: "May G-d bless you and
guard you... May G-d shine His countenance upon you and be gracious
to you... May G-d turn His face toward you, and grant you peace.

Yom Kippur atones for sins against G-d, but not for wrongdoings
between man and man. It is therefore important, on the day before Yom
Kippur, to apologize and seek forgiveness from friends, relatives,
and acquaintances, to heal any ill feelings which may have arisen.

Before the Mincha (afternoon) service it is a custom to give extra
Tzedaka.